Generally, a toothbrush used in conventional practices includes a flat plate-like header and bristles made of synthetic resin implanted on the header in such a manner as to be spaced apart from each other by a given distance, and accordingly, the bristles are different in length or diameter from each other so as to enhance the contact force with the teeth according to the curved surfaces of the teeth.
In the conventional practices, however, the bristles of the toothbrush are implanted erect on the flat plate-like header, and accordingly, the bristles are not elastically moved in accordance with the shapes of the teeth upon the tooth brushing, so that the contact area between the bristles and the teeth becomes small to cause the frictional forces of the bristles against the teeth to be not uniformly applied to the surfaces of the teeth when the tooth brushing is conducted, thereby undesirably decreasing the tooth brushing effects.